beforeconj.在 ... 以前pref.在 ... 以前;在..前面adv.以前;以往;之前
before the morning早晨来临之前
before competition赛前
Before Qin Dynasty先秦
before you know it不知不觉
before transfusion输血前
Before I arrive.我到以前。
before the days of;; ... 出现之前
before measurement前测
before water flood水驱前
before the meeting开会之前